The invention relates to a stopping device for a container equipped with a neck, as well as to a container provided with such a device. The invention also relates to a method for closing a batch of containers provided with a stopping device.
In the field of containers for medication, it is common to use a glass vial to preserve an active medicament in the form of lyophilizate, power or liquid solution. Such a vial must be closed in a dry manner in order to maintain its content in a satisfactory preserving state, until the date it is used. In order to hermetically seal a vial, it is common to use a stopping device that consists of a elastomer stopper and plastic cap intended to be fixedly attachable around the stopper to isolate the exterior.
WO-A-2007/063218 offers a stopping device, the cap of which consists of a ring and a body that allows maneuvering the locking means of the ring on the neck of a container. Moreover, WO-A-2008/129144 is known to integrate a deformable transmission element with thrust force into a stopping device which is intended to fade when a thrust force has been sufficiently transmitted to bring a body into a position where it activates the locking means of a cap on the neck of a container. FR-A-2-927-316 discloses the use of a connecting web which connects a peripheral press rim to a central stud and which has a different stiffness over different deformation ranges. FR-A-2 908 396 offers a stopping device in which a ring has a curbed extremity towards the exterior and cooperates with an internal peripheral groove of a ring to maintain locking means in an fixed position of the stopping device. These known devices offer overall satisfaction, particularly when they are used on vials, of which the neck has a diameter of 20 mm.
When these stopping devices are used to seal vials that belong to a batch of vials installed within a freeze-drier, by exercising a thrust force divided over the different stopping devices to bring them into a closed configuration, the thrust force exercised by means of a common body called “pressure plate” is divided over the different stopping devices. When containers with a relatively small diameter, particularly containers with a neck of a diameter of 13 mm, are used it is economically desirable to install a batch of containers previously equipped with stopping devices in a freeze-drier with the largest number of containers possible. In this case, the combined thrust force that is exercised by the pressure plate on each stopping device has a relatively weak intensity, equal to 25 Newtons for a classic freeze-drier. Under these conditions, it is important to minimize the necessary force to bring each stopping device into its usable configuration where it efficiently closes the neck of a container.
The present invention is directed to this problem by offering a stopping device in which the necessary force to bring the device into a usable configuration is minimized.
In this regard, the invention relates to a stopping device of a container provided with a neck, whereby this device contains a stopper and plastic cap, suitable for covering both the neck and the stopper in place on the neck, whereby this cap consists of a ring, suitable for surrounding the stopper and the neck in mounted configuration and provided with locking means on the neck, as well as a handling body of the ring, suitable to be mounted on the ring and provided with a thrust transmitting means for transmission to the ring a thrust force and a locking activation means for activating the locking means of the ring, while the ring and handling body, respectively, are provided with ring retainers and a holding position retaining means that cooperate together to maintain the handling body in a holding position in relation to the ring, where the handling body does not activate the locking means of the ring. In conformity with the invention, in a first position relative to the ring, the handling body is mobile in translation only in the direction of the thrust force, and a second position where the handling body activates the locking means of the ring and where the handling body is immobilized in relation to the ring in axial translation, according to a direction that is parallel to the thrust force, while the handling body comprises a first cylindrical surface with a constant radius or in the shape of an outwardly-inclined, radially inwardly-facing surface arranged facing the ring retainers of the ring, on the course of travel of the handling body between its first and second positions, and a second cylindrical surface with a constant radius or in the shape of an outwardly-inclined, radially inwardly-facing surface arranged facing the locking means of the ring, on the course of travel of the handling body between its first and second positions. Additionally, the locking means of the ring comprise locking tabs that extend from a first continuous edge of this ring, in the direction of the second edge of the ring opposite its first edge, while the diameter of a circle that circumscribes the external radial parts of the locking tabs has a greater value than the external diameter of the first edge and that each tab is arranged in an opening with closed contour which crosses the ring according to a radial direction in relation to a longitudinal and central axis of this ring.